A. The PowerShell modules for Server 2008 R2 are designed to run only against Server 2008 R2 clusters. Some functions may work if you use these modules against a Server 2008 cluster, but this is unsupported. I did some limited testing and most functions seem to work with no problems, but Server 2008 R2-specific functionality, such as Live Migration, Cluster Shared Volumes, and performance counters, obviously won't be available when working against a Server 2008 cluster.

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